The present invention relates to a powered gait orthosis, and more particularly to a device to aid in research and rehabilitation of non-ambulatory patients and provide therapeutic exercise for those with spinal cord injuries, neurological impairments and those recovering from orthopedic procedures. The invention also enables the measurement of outcomes and records patient session data for progress analysis.
Prior art devices for similar purposes are often not of sanitary construction and may require special electrical power sources and excessive site preparation. Additionally, such devices may be difficult to ship and setup. The prior art often requires the presence of more than one trained operator, thereby increasing the cost of such therapy. Additionally, therapists often perform portions of the therapy manually which does not result in uniform reproducible therapy to the patient. Prior art devices do not always provide easy patient access, and the devices may not successfully simulate a natural walking motion in the patients legs.
The present invention is of sanitary construction since it utilizes components formed of steel and aluminum. The components are shipped in disassembled arrangement, and are then bolted together on site, thereby facilitating shipping and setup of the device. The devices is self-contained and free standing, requiring only common electrical power sources and minimal site preparation. A single technician is required to operate the invention. When a patient is properly position and attached to the device, movement of the legs is performed robotically by the device, and no manipulation of a patient""s leg by a technician or therapist is required. However, the technician operating the device can adjust the operation of the components thereof in accordance with the requirements of different patients. The device has been successful in simulating a natural walking motion in legs of patients.
A powered lifting device is provided for lifting a patient from a wheelchair and transporting him to a position over a treadmill, whereupon he may be lowered onto the treadmill. Similar leg actuator assemblies are disposed at opposite sides of the treadmill, each assembly including a support arm which is pivoted for movement away from the treadmill to facilitate access to the treadmill. Each support arm pivotally supports a first depending arm from which a second depending arm is pivotally supported. A pair of servo motors are supported by each support arm and are drivingly connected to the first and second depending arms to independently move the depending arms about the pivot axes thereof. A first attachment means is adjustably carried by the first depending arm for attachment to a patient""s leg just above the knee; and a second attachment means is adjustably carried by the second depending arm for attachment of a patient""s leg at the ankle.
Each of the support arms is vertically adjustable independently of the other. The attachment means on the first and second depending arms are vertically and horizontally adjustable relative to the depending arm on which they are mounted. A control means includes a computer electrically connected to the drive means for the treadmill and the servo motors which operate the first and second depending arms so that the treadmill as well as the depending arms at opposite sides of the treadmill will operate in a coordinated manner to cause the legs of the a patient to move in a desired gait. Connected to the computer is an operator friendly touch screen interface with the ability to input, monitor and record pertinent data.
Sensor means is also provided for sensing the home position of each second depending arm and for sensing over-travel of such second depending arms and the knee joints of the device to thereby prevent damage to the knees of a patient. Locking devices are provided for locking the powered lifting means in position and for locking the support arms in position. The lifting means also includes load cells for measuring the weight of a patient suspended thereby.
When using the invention, a patient is initially fitted with a special harness and is lifted from a wheelchair to a standing position where weight is measured. A database containing individual set-up and historical information will be displayed on the touch screen. The patient is then moved over the treadmill and lowered thereon. The gait assist mechanisms are then attached to one or both legs of the patient. The percent of supported body weight can be adjusted as required as muscle strength of the patient develops. All component speeds are synchronized and controlled by operator input with treadmill speeds ranging from 0 to 2 mph. During a session, information such as blood pressure, heart rate, blood oxygen content, treadmill speed, session duration, etc. can be displayed and recorded for further analysis.